Optical devices, bioanalytical assays, and biological imaging probes often utilize components that exhibit optical properties, such as organic fluorophores and semi-conductor nanoparticles. Some desired optical properties include long luminescence lifetimes, large effective energy differences between excitation and emission bands, and sharp emission bands throughout the visible and near-infrared (NIR) spectral ranges. Lanthanide ions (Ln3+) contain unique 4f orbitals and exhibit unique luminescent characteristics that include sharp emission bands throughout the visible and near-infrared (NIR) spectral regions. However, the f-f transitions of Ln3+ ions are Laporte forbidden with low absorption coefficients, resulting in inefficient direct excitation and requiring sensitization with an appropriate antenna.